1. Field of Invention
The present invention relates to cranes in general and in particular to a method and apparatus for protecting the free distal end of a crane hoist line.
2. Description of Related Art
Cranes lift objects by way of their hoist line. The distal end of a hoist line frequently has a hook, weighted ball or other object attached thereto. One conventional method of securing objects to the distal end of a hoist line is through the use of a socket and wedge assembly 12 as illustrated in FIG. 1. A socket and wedge assembly 12 is suspended from a wire rope 10 or cable. The wire rope 10 may also comprise any other known flexible tensile member. As illustrated in FIG. 1, the cable 10 has a first or load bearing portion 8 suspended from the crane (not shown) and a second portion 6 being a free distal end supporting a socket and wedge assembly 12 therebetween.
The socket and wedge assembly 12 has a socket body 18 having a load end 14 and a top end 16. The socket body 18 has an internal cavity 20 adapted to receive the wedge 26 and cable 10 therein. The cavity 20 extends between top and bottom openings, 22 and 24, respectively. Such a connection is created by threading the cable 10 into a top opening 22 of the cavity 20, looping it around the wedge 26, and then pulling the free distal end 6 of the cable 10 back up into the socket again as illustrated in FIG. 2. The wedge 26 may then be secured around the wire rope 10 by either pulling down on the socket body 18 or pushing the wedge upwardly into the cavity 20. A clip 28 or other securing method may be then utilized to secure the free distal end 6 cable to either a top portion of the wedge or to the load bearing portion 8 of the cable 10.
Socket and wedge connections are common and popular in many applications as they are relatively quick and easy to install. Other similar connectors for a cable or wire rope are also common in which an object is secure to the a location proximate to the end of cable. In many of these methods, the cable will be doubled back upon itself after connection to the object as illustrated in FIG. 1.
Problems currently exist with the above conventional socket and wedge assembly as illustrated in FIGS. 1 and 2. Specifically, permitting the free distal end 6 of cable 10 to remain free permits it to encounter debris and other objects upon which the crane operator is manipulating. In particular, when a headache is suspended from the load end 14 of the socket and wedge assembly 12, the free distal end 6 of the cable is prone to impacting objects upon which the crane operator is applying the headache ball. Such impacts are known to fray or otherwise damage then end of the cable which impedes connection and disconnection of a socket and wedge to the cable without requiring repairs to the cable which are time consuming and difficult.
Additionally, the free distal end of the cable may be prone to catching on or damaging other structures as well as potentially injuring people who may come into inadvertent contact with the frayed end of the cable. Such catching on objects may also hang up the cable and caused a sudden deceleration to the crane cable, or shock load.
Previous attempts, including tape, brazing, or seizing it with wire to protect the free end of the cable have not been satisfactory. Such attempts have been difficult and time consuming to apply and have not prevented the free end of the cable or other components of the cable and socket and wedge assembly from catching on other objects and people.